Ultra-thin monocrystalline silicon solar cells are attractive because of their potential to achieve high efficiency operation and efficient materials utilization, in forms that are mechanically flexible and lightweight. The high natural abundance of silicon, its excellent reliability and good efficiency in solar cells, it suggests it is great material in production of solar energy. In advanced photovoltaic systems, many chances continue to happen for research into unconventional means of exploiting silicon. Here, we describe an experiment that uses large-scale silicon of the membrane of silicon solar cells created from bulk wafers and integrated in a variety of layouts on foreign substrates by transfer printing. I also present the design and fabrication of cells of this type, in which bulk wafers serve as sources of material for ~3 um thick bars of silicon that include patterns of surface relief, antireflection coatings and back reflectors collectively configured to maximize absorption via trapping of light. We can obtain a flexible or stretchable type of electronics, and low cost production that cannot be achieved in conventional electronic devices. We are able to fabricate 90% areal density of electronics with SOI wafer. Previously we reported Si <111>solar cells with an areal density of 60%. However, we have created more types of arrays that are flexible and having more than 86% of areal density. The final devices can offer useful features, including freedom of mechanical flexibility, ultrathin-form-factor microconcentrator designs. Since silicon-based electromechanical sensor technologies are in widespread use in various applications, we will also present a strain sensor. Typically, silicon-based sensors are fabricated into small packages with microelectronic integrated circuits for signal manipulation and recording. However, devices in this form are incompatible with certain applications in structural health monitoring for aircraft and in interfaces to the human body, where large-area large-scale intergrated networks of sensors on thin deformable substrates are required. We will show integration strategies, mechanical modeling results, and system demonstrations of distributed networks of strain sensors based on ultrathin single-crystalline silicon membranes bonded to thin plastic substrates. It offers high sensitivity of single crystalline silicon while providing lightweight construction and mechanical flexibility.